Survival and physiological responses of hybrid catfish during handling and transport activities

ABSTRACT Objective The hybrid catfish (male Blue Catfish Ictalurus furcatus × female Channel Catfish Ictalurus punctatus) is rapidly replacing the Channel Catfish as the fish of choice in the catfish industry of the southern United States. The objective of this study was to characterize survival and physiological responses in market-size (0.6–1.8 kg) hybrid catfish during capture from ponds and transport and before unloading them at a processing plant. Methods Ten commercial harvest and transport events were monitored over a year, allowing water temperature also to be considered. Survival and blood chemistries related to the stress response were monitored. Results All the fish survived seining, holding, transport, and unloading. Plasma cortisol, glucose, and lactate levels generally increased from harvest to arrival at the processing plant, whereas plasma osmolality remained unchanged. The fish that were harvested from warmer temperatures (25–32°C) demonstrated higher plasma glucose, lactate, and osmolality values than those that were harvested from cooler temperatures (9–16°C). Conclusions It appears that hybrid catfish tolerate harvest and transport well. The fish survived, demonstrated expected primary and secondary stress responses, appeared to remain largely aerobic during the events, and maintained acceptable water balance.